Barely a day goes by when proponents of greater taxation, universal income and other initiatives aimed at addressing systematic inequality are not accused of inciting the “politics of envy”. Doing so is an effective way of closing down debate; envy is, after all, among the deadliest of the “deadly sins”.

Yet politicians inclined to dismiss inequality in this way may do so at their peril. For the evidence of our hunting and gathering ancestors suggests we are hard-wired to respond viscerally to inequality.

In the 1960s, the Ju/’hoansi “Bushmen” of the Kalahari desert became famous for turning established views of social evolution on their head. But their contribution to our understanding of the human story is far more important than simply making us rethink our past.

Until then, it had been widely believed that hunter gatherers endured a near-constant battle against starvation. But when a young Canadian anthropologist, Richard B Lee, conducted a series of simple economic input-output analyses of the Ju/’hoansi as they went about their daily lives, he found not only did they make a good living from hunting and gathering, but they did so on the basis of only 15 hours’ work per week. On the strength of this, anthropologists redubbed hunter-gatherers “the original affluent society”.

I started working with Ju/’hoansi in the early 1990s. By then, more than a half-century of land dispossession meant that, other than in a few remote areas, they formed a highly marginalised underclass eking out a living on the dismal fringes of an ever-expanding global economy. I have been documenting their often traumatic encounters with modernity ever since.

The importance of understanding how hunter-gatherers made such a good living has only recently come to light, thanks to a sequence of genomic studies and archaeological discoveries. These show that the broader Bushmen population (referred to collectively as Khoisan) are far older than we had ever imagined, and have been hunting and gathering continuously in southern Africa for well over 150,000 years.

If the success of a civilisation is judged by its endurance over time, this means the Khoisan are by far the most successful, stable and sustainable civilisation in human history.

The speed of the Ju/’hoansi’s transformation from an isolated group of hunter-gatherers to a marginalised minority in a rapidly developing nation state is without parallel in modern history. As bewildering as this process has been for them, it offers a unique, if ephemeral, double-perspective – of people who are part of a modern globalised economy yet excluded from full participation in it, and who are engaging with modernity with the hands and minds of hunter-gatherers.

Taken together with new archaeological and genomic evidence, this brings fascinating insights into how to respond to some of the most pressing social, economic and environmental sustainability challenges we face today.

Among the most important is the realisation that apparently selfish traits such as envy – through which we express our discontent with inequality – was a useful evolutionary characteristic for building the social cohesion that enabled hunter-gatherers such as the Ju/’haonsi to thrive for as long as they did.

In part, the Ju/’hoansi’s affluence was based on their unyielding confidence in the providence of their environments and their skills at exploiting this. Ju/’hoansi still make use of well over 150 different plant species, and have the knowledge to hunt and trap pretty much any animal they choose to. As a result, they only ever worked to meet their immediate needs, did not store surpluses, and never harvested more than they could eat in the short term.

For the Ju/’hoansi, that fundamental axiom of modern economics, “the problem of scarcity”, simply did not apply. Where this holds that it is human nature to have infinite wants and limited means, the Ju/’hoansi had few wants that were simply met.

This was possible because, above all, they were – and still are – “fiercely egalitarian” . They could not abide inequality or showing off, and had no formalised leadership institutions. Men and women enjoyed equal decision making powers, children played largely non-competitive games in mixed age groups, and the elderly, while treated with great affection, were not afforded any special privileges. This in turn meant that no-one bothered to accumulate wealth or influence, and never over-exploited their marginal environment.

There is no question this dynamic proved effective. Over and above their extraordinary longevity, genomic evidence reveals that not only were the Khoisan the most populous human population on the planet until a little over 20,000 years ago, they also remain the most genetically diverse. This tells us that over their long history, Khoisan populations have suffered far fewer of the catastrophic population bottlenecks that are the result of famine, war and disease as other human populations elsewhere.

Crucially, their success was based not on their ability to expand and grow into new lands or develop new productive technologies, but on the fact they mastered the art of making a good living where they were. It is no coincidence that the continent with the evidence of the longest continuous human habitation is the only place unaffected by the extinction events that put paid 75% of the megafauna species – including mammoths, cave bears and sabre-tooth cats – when Homo sapiens expanded into Europe, Asia and the Americas.

How did a society like the Ju/’hoansi with no formalised leaders maintain this egalitarianism? Their answer is unequivocal: it was not born of the ideological dogmatism we associate with 20th-century Marxism, or the starry-eyed idealism of New Age “communalism”. Nor was it maintained in spite of self-interest – but rather, because of it.

Insulting the meat

In Ju/’hoan society, envy functioned like the “invisible hand” famously imagined by the economist Adam Smith. In the case of small-scale hunter-gatherer societies, the sum of individual self-interests ultimately ensured the most equitable “distribution of the necessaries of life”, and in doing so created the most sustainable economic model in modern Homo sapiens history.

How this worked is best exemplified in the customary “insulting” of a hunter’s meat. While a spectacular kill was always cause for celebration, the hunter responsible would not be praised – instead, he was insulted.

Regardless of the size or condition of the carcass, those due a share of the meat would complain that the kill was trifling, that it was barely worth the effort of carrying it back to camp, or that there wouldn’t be enough meat to go around. For his part, the hunter was expected to be almost apologetic when he presented the carcass.

Everyone knew the difference between a scrawny kill and a good one, of course, but nonetheless continued to pass insults even while they were busy filling their bellies with meat— the most highly prized of all foods. Half a century ago, a Ju/’hoan man provided Lee with a particularly eloquent explanation of why they did this:

“When a young man kills much meat, he comes to think of himself as a chief or a big man – and thinks of the rest of us as his servants or inferiors. We can’t accept this ... so we always speak of his meat as worthless. This way, we cool his heart and make him gentle.”

This behaviour was not limited to hunting. Similar insults were meted out to anyone who assumed airs and graces, encountered a windfall or got too big for their leather sandals. Everyone in Ju/’hoan communities scrutinised everybody else all the time — something easily done when all social life was conducted in public spaces.

They took careful note of what others ate, owned, received as gifts, and whether or not they were sufficiently generous in return. The net result was that everyone went to considerable lengths to avoid being singled out for selfishness or self-importance – so much so, indeed, that good hunters usually hunted less often than poor ones, even if they enjoyed it.

Unsurprisingly, this created an atmosphere that was generally harmonious, co-operative, and in which even those with the natural charisma and character to lead did so only with great circumspection.

In demonstrating why apparently corrosive vices such as envy survived the mill of natural selection, hunter-gatherer societies may also show why modern societies take pleasure in tearing down tall poppies; why gaudy displays of wealth are capable of persuading normally docile individuals to froth with rage, and why renegade politicians do so well when they position “elites” – real or imagined – as the architects of inequality.

The fact that hunter-gatherers such as the Ju/’hoansi enjoyed lives of “primitive affluence” suggests our current preoccupation with productivity and growth is not an indelible part of our “natures” – a preoccupation which, as environmental economists constantly remind us, risks cannibalising our species’ future.

As much as the Ju/’hoansi’s fierce egalitarianism served them well for so long, it poses a challenge now. They are by far the poorest and most marginalised of Namibia’s many distinct ethnic communities – yet they remain deeply uncomfortable elevating any of their peers to leadership positions.

Similarly, many Ju/’hoansi are reluctant to take management roles or assume responsibilities that require making and imposing their decisions or authority on others. As a result, they remain desperately under-represented in state institutions, meaning their interests are often overlooked and ignored.

Understanding how hunter-gatherers thrived for so long may help us identify the broad principles necessary to ensure a more sustainable future. Dealing with systemic inequality – not least, their own – would be a good place to start.

• Affluence Without Abundance by James Suzman (Bloomsbury Publishing) is available from the Guardian Bookshop at a saving of 15% on RRP
  
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